Carroll, a Republican who in 2010 became the first African-American to be elected to statewide office in Florida, had been a public relations consultant to the organization and was questioned but never charged.

State prosecutors called Mathis the mastermind of the operation, which called itself Allied Veterans of the World. Mathis and his associates allegedly hid the casinos behind a front business of Internet cafes. Customers allegedly bought time on the Internet but actually played the slots.

Veterans organizations saw almost none of the $300 million collected by Allied Veterans, prosecutors said.

Mathis was released on bond pending his sentencing Feb. 12. He faces as long as 100 years in prison on his convictions on one count of first-degree racketeering, a felony; 51 counts of third-degree operation of an illegal lottery, also a felony; and 51 counts of possession of illegal slot machines, a misdemeanor.

The jury deliberated for almost 15 hours over two days before returning the verdict at about 6:30 p.m. ET. It acquitted Mathis of just one of the 104 counts against him — a single charge of conspiracy.

Mathis called the verdict "unjust" and said he would appeal, telling reporters outside the courthouse that "attorneys all over the nation need to be very afraid when, six years after you give legal advice, somebody disagrees with you and convict you of a crime."

But state Attorney General Pam Bandi called the verdict "a strong message that those involved in running this illegal gambling scheme under the façade of a charitable organization to help veterans will be held accountable."

Other suspects who could face trial include Nelson Cuba and Robbie Frietas, the former president and vice president, respectively, of the Jacksonville Fraternal Order of Police.